Perhaps you should try some spelling variations:
"dung quang code snippets" » "dang quang code snippets", "luong quang code snippets", "dung luan code snippets", "dung quang de snippets", "dung quang code slippers"
"hoc sach code snippets" » "hoc sach che snippets", "hoc sach de snippets", "hoc sinh code snippets", "hoc cac code snippets", "hoc anh code snippets", "hoc sach code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("hoc sach code snippets") or ("dung quang code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hoc sach code snippets") OR ("dung quang code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hoc sach code snippets ) or ( dung quang code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hoc sach code snippets") or ("dung quang code snippets"))) or ("locating bug code snippets"))*.